1. Technical Field
The present invention generally relates to a paint composition and a related coating structure. The present invention also relates to a coating method for using the paint composition.
2. Description of Related Art
Paint is widely used for vehicle, furniture and electrical appliances. It is thus necessary for paint to be hard and smooth with good transparency whilst also having attractive color and appearance.
Conventionally, paint is composed of a resin matrix and an amount of pigment particles blended therein. The pigment particles are commonly an inorganic substance such as carbon black. Carbon black is a powdered form of elemental carbon manufactured by the vapour-phase pyrolysis of hydrocarbon mixtures, such as heavy petroleum distillates and residual oils, coal-tar products, natural gas and acetylene. Carbon black is characterized by the size distribution of the primary particles, the degree of their aggregation and agglomeration and the various chemicals adsorbed onto the surfaces. The color of carbon black is black because carbon black absorbs all incident visible light as well as UV light. The particle size of carbon black using in paint is commonly of a size in the micron range. A percentage of carbon black particles to the resin matrix by weight is generally in the approximate range from 5 percent to 6 percent.
However, the physical and chemical properties of inorganic pigment particles such as carbon black are quite different from that of the resin matrix, therefore, dissolution and dispersion of carbon black particles in the resin matrix is unsatisfactory. Thus, a surface having the paint composition coated thereon may be rough, and unsatisfactory in appearance. In addition, because the carbon black particles are simply mixed with the resin matrix without undergoing any reaction, physical force therebetween is very weak. Carbon black particles are often eroded out of the surface of product, thus creating cavities, which affect the mechanical properties and appearance of the coating.
What is needed, therefore, is a paint composition and a related coating structure with good smoothness, good transparency and high binding force.
What is also needed, therefore, is a coating method using the paint composition.